Workers initially feared the worst after they spotted the masked men with a pump-action shotgun raiding the shop as they turned up for work at around 6.30am local time.

Terrified members of staff were seen fleeing the Qwartz shopping mall in Villeneuve-la-Garenne, in the Hauts-de-Seine region to the northwest of the French capital, after the men arrived brandishing the weapon.

A crack unit of armed police were scrambled to the shopping centre after one worker managed to text their partner and tell them what had happened.

Around 18 workers were kept in the store while the men ransacked it, looking for cash.

Fears: Terrified staff were fleeing after seeing the men arrive (Image: Rex)

The staff inside were a mixture of shop floor workers, cleaners and others

No shots were heard, said the police source.

Officers at the scene said they were initially treating the incident as a 'suspected armed robbery attempt' but terrorism could not be ruled out.

A Paris police spokesman added: "The hostages were held at gunpoint for four hours.

"Our main priority was ensuring their safety and we have done this.

"The men fled and are being actively hunted. Police forces across the region have been alerted.

Siege: Armed police quickly arrived on the scene (Image: Rex)

"One hostage told us that she recognised one of the men as a former employee of that store.

"He and the other two were armed with pump-action rifles. We are very pleased to say no one was injured and all are now safe."

Despite getting all hostages out, police were unable to trace the gunmen, who it is thought fled soon after police were called.

Officers said there was no sign of any terrorist of political or other motive for the raid.

The Paris region remains on high alert for terrorist activity after Islamic extremists attacked a kosher supermarket and satirical newspaper offices in January, leaving 20 people dead, including the attackers.

Disappeared: The gunmen are now on the run after police could not find them (Image: Google)

RAID anti-terrorist police who attended the incident, were at the centre of the Charlie Hebdo attacks in January when three Islamist gunmen murdered 17 innocent people in Paris.

Four of the victims were Jews who were held up in a Kosher supermarket in Vincennes, in east Paris.

The Primark store is in the Qwartz shopping centre, which was shut down this morning, along with all roads leading towards it.

Terrorist groups including Islamic State and Al-Qaeda claimed responsibility for the attack against Charlie Hebdo, the satirical magazine.